One way of determining which advertisements should be placed on which pages is based on matches with textual data. However, text-based identification and matching limits the relevancy of ad placements. Since the same words can be used in different contexts, depending on the identified text, the advertisement identifier may need to parse through tens of thousands of advertisements which may be relevant. Also, in many contexts, particularly on social-network and photo sharing sites which rely on tagging, there is insufficient text for accurately identifying advertisements. Furthermore, since many related concepts or ideas do not necessarily have the same identifying keywords, some search results or recommendations which are relevant may be missed by the traditional text-based identification means.